Compared with straightline planting, the practice reduces fertilizer loss and increases crop yields on uneven terrain. These properties can either be adjusted right before adding the contour line to your landscape or after it has been added. Readingunderstanding topographic maps school of forest. Mark four points two on the endpoints, and two between and draw the contours. Contour lines contour line interpolation free 30day. All points in a contour line have the same elevation. Contour lines of different heights can never cross each other. Contour lines close together indicates a steep slope. Vertical distance between any two consecutive contours is known as the contour interval. Imaginary line joining points of equal elevation above or below a datum contour lines have a specific contour interval interval is the vertical distance between contours ci is a. Design of a supersonic nozzle using method of characteristics. Features of contour lines are helpful in plotting and interpretation of several features in the map.
There are many fields of interest in which contour analysis and visualization can be applied. The geospatial work flow section provides support in selecting methods for di. Every contour closes on itself either within or beyond the limits of the map. A contour line represents an imaginary line on the ground, above or below sea level. The contour lines in an area are drawn keeping difference in elevation of between two consecutive lines constant. On a map the contour lines will be spaced closer together with a decline in height above sealevel.
The physical characteristics of line the physical characteristics of line are many. In economics, contour lines can be used to describe features which vary. Contours show distinct characteristic features of the terrain as follows. Contour lines of different elevations cannot cross each other. Regression methodology for bivariate heteroscedastic data pdf. Evenly spaced contour lines indicate a uniform slope. Rule 5 contour lines are closer together in steep terrain and farther apart in flat.
Start with contour farming as a farmer, your first step for slowing down rainwater is to determine your fields contour lines. In this case, several contours coincide and the horizontal equivalent becomes zero. Contour line contour is a slow, intense inspection of parts. It is, however, unlike outline, which only states the outside edge of an object defining difference between positive and negative space. Basin characteristics from hydrological processes at the point scale to hydrological processes throughout the space continuum. Characteristics of contour lines, contouring, assignment help. Find animations helping students interpret hachured lines, contour spacing, and valleyridge placement. Draw a line between the two points bounding the desired profile area. Representing heights on maps professor keith clarke contours on maps. Langbein and others abstract river floods are the result of many causes, and one of the primary objectives of scientific hydrology is the segregation and evaluation of the causative factors.
Divide 300 feet by 3 to get one contour every 100 feet. The greater the distance between two contours the less the slope. Visualize the contour lines in 3 dimensional view application. Contour contour is an imaginary line on ground joining points of equal or constant elevations. All points on a contour line have the same elevation.
Each drawing below violates a rule of contour lines. A contour or a contour line may be defined as the line of intersection of a level surface with the surface of ground. A contour line of a function of two variables is a curve along which the function has a constant. Aug 23, 20 contour contour is an imaginary line on ground joining points of equal or constant elevations. The objectives of contour analysis and visualization can be described in the following stages 1. Predictions are based on measurements from nearby locations or time periods. They never cross, split or intersect at a cliff they might merge. Contour lines never run into one another except in the case of a vertical cliff. Pdf contour lines generation in karstic plateaus for. When a contour line is drawn on a map it represents a given elevation. Contours may pass through small, tightly grouped hydrographic features, such as sewage lagoons. Contour lines must close, not necessarily in the limits of the plan. A uniform slope is indicated when the contour lines are uniformly spaced and 4. The methods section includes information about the individual methods.
A plane surface when they are straight, parallel and equally spaced. Sep 29, 2017 contour lines, isolines, or isograms are used widely in different fields such as meteorology, geology, oceanography, and other sciences to represent lines with equal values of a certain attribute. Contour farming, the practice of tilling sloped land along lines of consistent elevation in order to conserve rainwater and to reduce soil losses from surface erosion. So two different contour lines cannot intersect or otherwise contact each other except at a point where a vertical or overhanging surface, such as a vertical or overhanging face of a cliff, exists. Specific names are most common in meteorology, where multiple maps with different variables may be viewed simultaneously. The principal characteristics of contour lines which help in plotting or reading a contour map are as follows. Contour lines types, characteristics and uses in surveying. There is even an animation that gives students practice. Contour lines can indicate the outer borders of the foot and suggest a threedimensional form. Hachures are short lines perpendicular to the contour line. Pdf a design of contour generation for topographic maps. Lines may be short or long, thin or thick, straight or curved, direct or meandering, zigzag or serpentine, distinct or blurred.
Concave slope a slope which becomes progressively steeper uphill. Farming across the slope helps to shorten slope lengths. Find contour lines lesson plans and teaching resources. Below is a description of each available property in the order that. The horizontal distance between any two contour lines indicates the amount of slope and varies inversely on the amount of slope. From each mark, indicate the vertical height with a dot on a scale. If it closes beyond the limits of the map it will run to the map edge. Contour lines are a key features of topographic maps as they make the comprehension of terrain more easy. They can be smooth or flowing, short or choppy, dark or light, broad or narrow. Every point on the map touching the line should be the same elevation. All points along the same contour line are at the same elevation. Contour lines cannot merge or cross one another on map except in the case of an overhanging cliff 9. In cartography, contour lines are an imaginary line of a terrain that joins the point of equal elevation above a given level, such as mean sea level or benchmark. On a map the contour lines will be spaced closer with an increase in height above sealevel.
This allows you to do all the land preparation, planting, and harvesting across the. A line drawn on a map or plan connecting points of equal elevation. Topographic characteristics of drainage basins by walter b. Closed contours with arrow in the centre represent depressions. Following are the characteristics of contour lines in surveying for reading contour maps. All elevation values and the resulting contour lines were cast. Use contour lines to determine elevations of mountains and. Flat ground is indicated where the contours are widely separated and steepslope where they run close together.
Flat ground is indicated where the contours are widely separated and. But they are no longer drawn by cartographers, they are mostly automatically derived from. Contour lines do not cross each other, divide or split. All contour lines eventually connect with themselves. On contour lines the level of lines is also written. Changing contours indicates a change of ground form. The closer together the contour lines appear on a topographic map, the steeper the slope assuming constant contour intervals. Then plant your crops across the slope or on the contour. Contour lines isolinesand imaginary line in the map. A point on a map or chart that has the elevation noted. All points on the contour line are at the same elevation. Characteristics of contours x contour lines 50 never run into one 40 another except in 30 the case of a 20 vertical cliff. The method of characteristics provides a technique for properly designing the contour of a supersonic nozzle for shock free, isentropic flow, taking into account the multidimensional flow inside the duct the purpose of.
Contour lines, isolines, or isograms are used widely in different fields such as meteorology, geology, oceanography, and other sciences to represent lines with equal values of a certain attribute. On some maps, numbers on the lines will let you know what the elevation is for that line. This allows you to do all the land preparation, planting, and harvesting across the slope. Contouring contouring contour definitions, objectives, contour interval, horizontal equivalent, uses and characteristics of contour lines, methods of plotting contours, direct and indirect methods of contouring, contour gradient. The change in elevation between one contour line and the next. The following are general characteristics of contour lines. Pdf contour lines are a key features of topographic maps as they make the comprehension of terrain more easy. The properties used to modify a contour line object are located to the right of the screen when your contour line is selected. This section describes the characteristics of interpolation methods in general.
So two different contour lines cannot intersect or otherwise contact each other except at a point where a vertical or overhanging surface, such as a vertical or overhanging face of a cliff, exists on the. Contour lines cannot merge or cross one another on map except in the case of an overhanging cliff. So two different contour lines cannot intersect or otherwise contact each other except at a point where a vertical or overhanging surface, such as a vertical or overhanging face of a cliff, exists on the ground figure 818 shows an overhanging cliff. It is, essentially, the outline or silhouette of a given object or figure. Contouringtopographic map preparation,uses and characteristics. Contour lines connect a series of points of equal elevation and are used to illustrate topography, or relief, on a map. In the world of art, a contour line is a line which defines a form or an edge. Characteristics of contours i all points in a contour line have the same elevation. Contour lines, sometimes called level lines, join points of equal elevation. Characteristics of contour lines a contour line is a line of equal elevation.
Topographic survey topographic survey the most common method of representing the topography of an area is to use contour lines contours a contour lineis an imaginary level line that connects points of equal elevation topographic survey there are several rules to note when viewing topographic maps. In a depression, the contour lines also form circles. Contour lines characteristics of contour lines are. Contour lines are the most common method of showing relief and elevation on a standard topographic map.
Topographic mapshave a variety of uses, from planning the best route for a hike to determining a location for a school or an airport. The closer together the lines are, the steeper the slope. The diagram illustrates how contour lines show relief by joining points of equal elevation. The distance between contour lines indicates the steepness of the slope. It depends upon the scale of the map, nature of the ground and. Contour elevation numbers indicate the direction of elevation by always reading pointing uphill. However, contour lines of different elevation intersect only in case of an overhanging cliff. Contour lines of different elevations can unite to form one line in case of a vertical cliff. A contour line is a single, clean, incisive line, which defines edges. Natural physical features topographical features of the site thru contour map site drainage existing natural features of trees size, type, diameter, height, spread of roots.
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